Long-range enhancer differentially regulated by c-Jun and JunD controls peptidylarginine deiminase-3 gene in keratinocytes.
Long-range cis elements are critical regulators of transcription, particularly for clustered paralogous genes. Such are the five PADI genes in 1p35-36 encoding peptidylarginine deiminases, which catalyze deimination, a Ca2+-dependent post-translational modification. Deimination has been implicated in the pathophysiology of severe human diseases such as multiple sclerosis and rheumatoid arthritis. The PADI genes present different expression patterns. PADI1-3 are expressed in the epidermis, with increased expression levels in the most differentiated keratinocytes. Previous studies on PADI proximal promoters failed to explain such specificity of expression. We identified a conserved intergenic sequence in the PADI locus (IG1), which may play a role in PADI transcriptional regulation. In this work, we identified two DNase I.hypersensitive sites located in IG1, PAD intergenic enhancer segment 1 (PIE-S1) and PIE-S2, which act in synergy as a bipartite enhancer of the PADI3 and probably PADI1 promoters in normal human epidermal keratinocytes differentiated by a high-calcium-containing medium (1.5 mM). PIE-S1 and PIE-S2 present all the hallmarks of transcriptional enhancers: orientation-independence, copy-number dependence and cell-type specificity. PIE-S1 and PIE-S2 comprise conserved putative binding sites for MIBP1/RFX1 and activator protein 1, respectively. Deletion mutant screening revealed that these sites are crucial for the enhancer activity. Furthermore, chromatin immunoprecipitation assays evidenced differential binding of JunD or c-Jun on the activator protein 1 site depending on the cell differentiation state. Our results reveal the molecular bases of the expression specificity of PADI1 and PADI3 during keratinocyte differentiation through a long-range enhancer and support a model of PADI gene regulation depending on c-Jun-JunD competition.
Adoue
Véronique
V
UMR 5165, CNRS-Toulouse III University, CHU Purpan, Place du Dr Baylac TSA4003, 31059 Toulouse cedex 9, France.
Chavanas
Stéphane
S
Coudane
Fanny
F
Méchin
Marie-Claire
MC
Caubet
Cécile
C
Ying
Shibo
S
Dong
Sijun
S
Duplan
Hélène
H
Charveron
Marie
M
Takahara
Hidenari
H
Serre
Guy
G
Simon
Michel
M
D001483:Base Sequence; D001665:Binding Sites; D002454:Cell Differentiation; D049109:Cell Proliferation; D047369:Chromatin Immunoprecipitation; D021901:DNA, Intergenic / Q000378:metabolism; D003850:Deoxyribonuclease I / Q000378:metabolism; D004742:Enhancer Elements, Genetic; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D006867:Hydrolases / Q000235:genetics*; D015603:Keratinocytes / Q000166:cytology / Q000201:enzymology* / Q000378:metabolism; D008156:Luciferases / Q000378:metabolism; D008957:Models, Genetic; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding; D000080062:Protein-Arginine Deiminase Type 1; D000080063:Protein-Arginine Deiminase Type 3; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism*; D018808:Transcription Factor AP-1 / Q000378:metabolism*; D014158:Transcription, Genetic
D021901:DNA, Intergenic; D016755:Proto-Oncogene Proteins c-jun; D018808:Transcription Factor AP-1; D008156:Luciferases; D006867:Hydrolases; D003850:Deoxyribonuclease I; D000080062:Protein-Arginine Deiminase Type 1; D000080063:Protein-Arginine Deiminase Type 3